Motor Memory And Minor Sense Impressions

"I am sure that if a fairy bade me choose between the sense of sight and that of touch, I would not part with the warm, endearing contact of human hands."

Some authorities hold the opinion that the two main memory channels, discussed in the preceding chapter, are the only ones worthy of consideration or cultivation. As for the other senses, " they will do their part without stimulus from us," says one writer. This may be true to some extent, but while in agreement with the opinion that the visual and aural are of paramount importance, I hold that the minor sense channels deserve at least some attention to their development. Especially is this true since we find every organ of sense with the possible exception of touch, more perfect in the brute than in man.

CLASSIFICATION OF MINOR IMPRESSIONS

We may classify under this head, the sense of touch or feeling, the sense of smell, and the sense of taste. Also a sixth sense which psychologists generally add to the five already mentioned, which may be called the muscular sense, which reveals the state of our muscles. Other minor sense impressions may be classified as feeling connected with the stomach, such as hunger, thirst, repletion, indigestion, or such as may, arise from diseased or abnormal states of particular sensory organs or tissues, such as inflammation, cramp, burns, bruises, etc. These minor sense impressions are the sources of much pleasure and pain to mankind, but while adding much to our experience, they add little to our higher knowledge. Fortunately each sensory organ is especially adapted to the reception of its proper stimulus, the nose for smell, the palate for taste, etc. Undoubtedly these sensations do much to aid the brain in its memory task, but we must never forget that they are only servants and that mind is the master. Here again we find that different people have different degrees of efficiency in these forms of memory. In some the memory of taste may be almost perfect, while the memory of smells is very deficient. Tea-tasters and wine connoisseurs are memory specialists in the sense of the palate. Others have a highly developed memory of heat or cold, or perhaps of the sense of equilibrium.

All these minor forms are very interesting, but not of primary importance in the human quest for knowledge, nor are they factors of much weight in a good memory course. With animals the case is entirely different.

" The bat has a sense of hearing so developed that it must be of first importance in the brain. The whole wondrously delicate membrane of the wings is capable of catching and hearing the subtle echoes from the slight noise of its own flight. Those reflections of sound are caught as they come from wall and tree and open spaces, and by them the distance of things is instantly known.. Such, at least, is a scientific explanation of the bat's ability to fly discreetly at full speed through absolute darkness. More familiar, is the predominance of the sense of smell in the dog, which depends on it, rather than on his eyes. For that reason, the dog, when he enters a strange place, runs sniffing about. That is his way of concentrating, of establishing sure memories. The beast smells the floor, the wainscoting, the feet of any humans present, and thus he secures:records for memory. When the dog lies dreaming, his brain is filled, not as yours or mine might be with a panorama of scenes out of his experience, but with a succession of smells: that of the field where he coursed, of the hare he followed, of the master he served."

But motor memory must not be ranked among the minor sense impressions. It is far more significant, and holds a much higher place. In fact, the ancient doctrine of Democritus asserted that all the senses are but modifications of the sense of touch. Some modern writers have elaborated this doctrine under the head of " Kinaesthesia." Helen Keller has written a marvelous book basing a complete philosophy of life 'on the touch of the hand.

How MOTOR MEMORY WORKS

I wish to make a very brief and practical application of -motor memory in the activities of every-day life. Referring to it as all that comes to us through the sense of touch, we find that it covers a wide scope. The clerk in the grocery store who sells many packages and parcels by weight soon becomes an adept. By the power of his motor sense he can " heft " a package, and often guess its exact weight, or within a few ounces of it.

The saleswoman who handles dress goods soon learns to distinguish linen, silk, cotton, and many other fabrics, simply by the touch, the feel of it. She knows what it is without seeing, because of the impressions previously recorded on the motor memory cells of the brain. She knows the texture of different goods and fabrics, and becomes a good judge of quality.

The typist, who manipulates the keys of the typewriter day after day, soon relies more on motor memory than on the visual. The musician with his marvelously trained fingers sweeping the keys of a piano, or fingering the strings of a violin as he makes his own keyboard, uses motor memory as a powerful aid to his highly developed aural memory. But after all, " It was not the hands that remembered; something higher up, the little grey engine, made improvement possible."